A Fringe Analysis Program

by Dave Rowe

FringeXP is a simple, easy-to-use fringe analysis program for the amateur. With it, one can load interferograms, enter and edit fringe points, and analyze mirror or optical system performance. It has auto-tracing capability, and can average multiple sets of Zernike Coefficients from separate interferogram analyses. Even if you never intend to build an interferometer, you may enjoy trying the program and reading the Help section. Sample interferograms are provided for this purpose.

System Requirements:

FringeXP works with Windows 95, 98 and XP operating systems. It requires a minimum screen resolution of 1024 X 768 pixels and approximately 10 MB of RAM.


• Auto-tracing of fringes
• Fringe point editing and optimization
• Simple aperture definition
• Zernike averaging from multiple interferograms
• Color contour and section plots of wavefront errors
• Numerical nulling for non-spherical mirrors
• Report generation
• A "getting started" Help section

Sample Program Output:

Contour Plot of Surface Error


FringeXP is provided as freeware. Please do not distribute the program to anyone. Direct interested parties to this URL for the latest version. The current version of the program is 2.0, compiled on 10/16/03.

To download the executable file, FringeXP.exe, click here. (300K)

To download a Zip file containing FringeXP and four sample interferograms taken by James Lerch, click here. (990K)
The ReadMe.txt file in this archive contains the mirror information for the sample interferograms.

Getting Started:

FringeXP contains a Help section to get you started. Please read it carefully, especially the section by Peter Ceravolo. This section contains very important information on some of the limitations of the program, and some useful advice on interferometry.

Peter John Smith has created a document with several worked examples. This will help you understand some of the workings of the program, and how to interpret program output. click here.

Peter Ceravolo has written an excellent document on interferometry for the amateur. click here.


During the development of FringeXP I received extensive help, advice and testing from Peter John Smith, James Lerch, Vladimir Galogaza, Steve Koehler, Mark Suchting and Mike Peck. Bugs that still remain in the program are mine and mine alone.

Contact the Author:

Comments, suggestions and bug reports should be addressed to Dave Rowe If you use the program, I’d like to hear from you. Thanks.


Although program accuracy has been checked for many sample interferograms, the author makes no claims, either direct or implied, regarding the suitability or accuracy of this software for your application. Use this program at your own risk.

May heaven’s air be still and crystal bright
While vision drinks this dark and starry night.